Abstract
This paper discusses an estimation method of auto frequency response function using additional masses. The input forces in vibration testing cannot be applied to the excitation points of the structure, if it is difficult to secure space for excitation to structures with complex shapes. In order to improve the accuracy of estimated unmeasured frequency response function, maximum likelihood method for reducing random noise effect is introduced in this method. Additionally, reliability factor of the estimated unmeasured frequency response function is obtained by considering the propagation of random noise from measured frequency response functions. The feasibility of the method is verified by comparing the unmeasured frequency response function of a lower arm that is a part of car's suspension system estimated by the method and obtained by impact testing.
